The present invention relates to a control system for the heating system of an automobile, and especially to a self-checking control system and method and indicating circuit which repeatedly performs the self-checking steps to detect problems in the heating system. When problems are detected by the control circuit, the control system stops the control process, and simultaneously gives a warning indication of a disordering state in the process of control.
Heating systems for automobiles are known which combine heating and preheating of the engine by including a special heating system, separate from the conventional heating system which uses the waste heat from the water of the engine coolant system. These types of heating systems are used in long distance cars, as well as in all types of ordinary cars.
Conventionally, in systems for detecting the cause of heating system problems, such as heater trouble, circular pump trouble, and battery deficiencies, the display of the trouble is usually restricted by using a fundamental sensor means to drive the sensor system. Minor displayers are used to display the cause of the trouble, depending on the type of trouble detected.
Accordingly, the range of trouble indication was broad, and the individual respective states of the various systems (i.e., the heater, circular pump or battery) could not be known. Furthermore, if the step of detection passed a system during the sequential control, it was possible to detect problems only when the systems are repeatedly checked.
These problems in the conventional systems induced misunderstandings in the user's mind as to the cause of the trouble. Even more alarming, the deficiencies in the conventional systems are potentially dangerous.
The principal concept of the present invention is similar to that described in Korean Patent Application No. 88-7980.